CHICAGO (NewsNation Now) — The number of Americans seeking unemployment benefits increased slightly last week.

The Labor Department said Thursday that jobless claims increased by 4,000 the previous week to 353,000. Claims prior to this had dropped for four straight weeks, hitting pandemic lows.

The weekly count has fallen more or less steadily since topping 900,000 in early January as the rollout of COVID-19 vaccines has helped the economy — encouraging businesses to reopen or expand hours and luring consumers out of their homes to restaurants, bars and shops.

Adjusting the data for seasonal fluctuations is tricky around this time of the year, a task that has been complicated by the pandemic. That could account for the increase in applications last week.

But a resurgence of cases linked to the highly contagious delta variant has clouded the economic outlook. And claims already remain high by historic standards: Before the pandemic tore through the economy in March 2020, the weekly pace amounted to around 220,000 a week.

Filings for unemployment benefits have traditionally been seen as a real-time measure of the job market’s health, but their reliability has deteriorated during the pandemic. In many states, the weekly figures have been inflated by fraud and by multiple filings from unemployed Americans as they navigate bureaucratic hurdles to try to obtain benefits. Those complications help explain why the pace of applications remains comparatively high.

At least 25 states led by Republican governors have pulled out of federal government-funded unemployment programs, including a $300 weekly check, which businesses claimed were encouraging unemployed Americans to stay at home.

There is, however, no evidence that the early termination of federal benefits has led to an increase in hiring in these states. The government-funded benefits will expire on Sept. 6.

Companies are clinging to their workers amid a labor shortage. Lack of child care facilities and fears of contracting the virus have been blamed for worker shortages, which are partly contributing to employment remaining 5.7 million jobs below its peak in February 2020. There were a record 10.1 million job openings as of the end of June.

Whatever the causes, the economy remains 5.7 million jobs shy of what it had in February 2020.